You can use this data confidently. Stats NZ rated it as high quality.
For more information, read about response rates below.
Stats NZ gives data an overall rating based on sources and coverage, consistency, and data quality.
Why am I seeing this?
This data is from the Census. The past two censuses had relatively low response rates, particularly for some areas of New Zealand and groups of people.
Where information was missing or unreadable, Stats NZ attempted to use data from a range of places such as previous censuses or administrative data that is collected by other government agencies. If that isn't available, Stats NZ use statistical models to predict what the missing data would have been. This is called imputation.
Things to be aware of
A person may vary their reporting of their ethnicity, including the number of ethnicities they identify with, according to the context in which they are asked. This is a consideration when comparing the 2023 Census results with other sources. For the 2023 Census, changes to the online form as-you-type list were made to encourage more specific responses.
Ethnicity is the ethnic group or groups a person identifies with or has a sense of belonging to. It is a measure of cultural affiliation (in contrast to race, ancestry, nationality, or citizenship). This demographic attribute is self-perceived, and a person can belong to more than one ethnic group.
Response rates and final data sources
Ethnic group:
The response rate for this question from 2023 Census forms was 86.0%. A further 8.8% of the data come from responses to the previous Censuses. Administrative data made up 4.4% of the response while the remaining 0.8% of the data was derived from statistical imputation.
Age group:
The response rate from 2023 Census forms was 89.7%. The remaining 10.2% of responses were sourced from administrative records and 0.1% from statistical imputation.
Definitions
Census usually resident population count of New Zealand: a count of all people who usually live in and were present in New Zealand on census night. It excludes overseas visitors and New Zealand residents who are temporarily overseas.
Geographically the census includes the North Island, South Island, Stewart Island, and the Chatham Islands, plus largely uninhabited islands including the Kermadec Islands, Three Kings Islands, Mayor Island, Motiti Island, White Island, Moutohora Island, Bounty Islands, Snares Islands, Antipodes Islands, Auckland Islands, and Campbell Island.
Changes to data collection/processing
A break in time series occurred between the 2013 and 2018 Censuses due to the adoption of a combined census model as a mitigation to lower-than-expected response rates in 2018. This model improved the enumeration of traditionally low responding age groups, such as young adults. The 2023 Census uses a combined model by design. The population counts show very high consistency with the 2018 Census, and less consistency with the 2013 Census due to the change in census model.
The New Zealand Census of Population and Dwellings is the official count of how many people and dwellings there are in New Zealand. It provides a snapshot of our society at a point in time and helps to tell the story of its social and economic change. The 2023 Census, held on Tuesday 7 March, was the 35th New Zealand Census of Population and Dwellings. The first official census was run in 1851, and since 1877 there has been a census every five years, with only four exceptions.
Purpose of collection
Census information is used by government agencies, local authorities, businesses, community organisations, and the public for developing and implementing new policies, research, planning, and decision-making. It helps us make decisions about how to best use public funding, especially in areas of health, education, housing, and transport.
The census is also the primary source of information used for deciding the number of general and Māori electorates, along with data from the corresponding Māori Electoral Option.
Method of collection/Data provider
The response rate from 2018 Census forms was 89.1%. The remaining 10.9% of responses were sourced from administrative records.
Admin-enumerated records were added to the census file to count people who were missed.